[mabarker1]

The Rio Bravo provides a lot of natural border. Its not impenetrable but it is a deterrent.

Are You refering to the movie Rio Bravo or The Hotel or The Rio Grande River the Natural flowing river between Texas and mexico ?

[deport]

South of the border it is known as the Rio Bravo.
Not sure how that got inserted in the article.

[Don Corleone]

Ther Rio grande is also called the Rio Bravo.